N-doped polymer-derived Si(N)OC: The role of the N-containing precursor

Abstract

Polymer precursors for Si(N)OC ceramics have been synthesized by hydrosilylation reaction of polyhydridomethylsiloxane (PHMS) with three different nitrogen containing compounds. The results obtained by combining characterization techniques such as FTIR, 13 C-and 29 Si-NMR confirm the occurrence of the cross-linking reaction between Si-H and vinyl groups. The structural characterization of the corresponding ceramic phase shows that the type of N-containing compounds strongly influences the pyrolytic transformation as well as the crystallization behavior of the final ceramics. Elemental analysis clearly indicates that N is present in the Si(N)OC matrix and the degree of N retention after pyrolysis is related to the type of N-containing starting compound. XPS data show that N-C bonds are present in the Si(N)OC ceramic samples even if only N-Si bonds are present in the starting N-containing precursors. However, if nitrogen atoms form bonds with sp 2 carbon atoms in the preceramic polymer then a larger fraction of C-N bonds is retained in the final Si(N)OC ceramic.

Polymer‐derived ceramic aerogels as sorbent materials for the removal of organic dyes from aqueous solutions

“…In our laboratory, porous PDCs aerogels showing hierarchical porosity ranging from some microns to few nanometers and with high SSA in the range 100‐700 m 2 /g have been recently synthesized . Moreover, their structure contains different types of chemical bonds (Si–O, Si–N, Si–C, C=C, C=O) and functional groups (OH, NH, COOH) depending on the composition and pyrolysis atmosphere . This unique combination of hierarchical porosity, high SSA and broad range of surface chemical functionalities makes the PDC aerogels ideal candidates as sorbent materials for water purification.…”

“…42 Moreover, their structure contains different types of chemical bonds (Si-O, Si-N, Si-C, C=C, C=O) and functional groups (OH, NH, COOH) depending on the composition and pyrolysis atmosphere. 23,24,43 This unique combination of hierarchical porosity, high SSA and broad range of surface chemical functionalities makes the PDC aerogels ideal candidates as sorbent materials for water purification. In this work, we proposed to use SiC, SiOC aerogels, and a PDC SiC foam as adsorbents for organic dyes to purify contaminated water and we compared their behavior with a commercial mesoporous silica.…”

Novel Sulfur‐Containing Cross‐Linking Agent for Si‐Based Preceramic Polymers

“…For the polymeric aerogel, the derivative indicates a range of high mass loss from 380 to 520 °C with a maximum at 450 °C. This behavior is characteristic for PMHS cross‐linked with either tetramethyl‐tetravinyl‐cyclotetrasiloxane (TMTV) or 1,3,5‐triallyl‐1,3,5‐triazine‐2,4,6 (1 H ,3 H ,5 H )‐trione (TTT) . In comparison to the derivatives of mass loss for pure DVT and PMHS with maxima at 404 and 402 °C, respectively, the polymeric PMHS‐DVT aerogel shows greater thermal stability with mass loss shifted by 50 °C toward higher temperatures.…”

“…This behavior is characteristic for PMHS cross-linked with either tetramethyl-tetravinyl-cyclotetrasiloxane (TMTV) or 1,3,5-triallyl-1,3,5-triazine-2,4,6 (1H,3H,5H)-trione (TTT). [33,37] In comparison to the derivatives of mass loss for pure DVT and PMHS with maxima at 404 and 402 °C, respectively, the polymeric PMHS-DVT aerogel shows greater thermal stability with mass loss shifted by 50 °C toward higher temperatures. This indicated the thermal stability of the PMHS-DVT aerogel is enhanced by its cross-linking network.…”

Thermodynamics of amorphous SiN(O)H dielectric films synthesized by plasma‐enhanced chemical vapor deposition

“…Oxynitride glasses, glass ceramics, and coatings containing all three elements are slightly more common owing primarily to the improved thermal, mechanical, and chemical properties afforded by the addition of nitrogen to oxide glasses . However, the addition of a fourth element—hydrogen (eg a‐SiONH) via various polymer‐derived, thermal, and plasma‐enhanced chemical vapor deposition (PECVD) methods leads to a much more diverse array of technologically important materials and applications. Thin films of a‐SiO x , a‐SiNH, and a‐SiNOH are also extensively utilized in the semiconductor industry for a wide variety of electronic, optoelectronic, photovoltaic, thermal, mechanical, micro‐electromechanical, and biological applications to create surface passivation, solid‐state electrolytes, anti‐reflection coatings, membranes, gate dielectrics, etch stops, diffusion barriers, moisture sensors, micromechanical cantilevers, and biomineralization layers .…”